BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

Integer and Statistic

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Senior | Next Rank: 100 Posts
Posts: 32
Joined: Fri Sep 17, 2010 4:01 am

Integer and Statistic

by Veronica » Mon Sep 20, 2010 11:48 pm
If the units digit of the three-digit positive integer k is nonzero, what is the tens digit of k?
1. The tens digit of k + 9 is 3
2. The tens digit of k + 4 is 2

Tom, Jane, and Sue each purchased a new house. The average price of the three houses was 120,000. What was the median price of the three houses?
1. The price of Tom's house was 110,000
2. The price of Jane's house was 120,000
Top
Source: — Data Sufficiency |
Newbie | Next Rank: 10 Posts
Posts: 9
Joined: Tue Mar 24, 2009 7:11 pm

by neel_mutum » Tue Sep 21, 2010 12:42 am
Question:
If the units digit of the three-digit positive integer k is nonzero, what is the tens digit of k?
1. The tens digit of k + 9 is 3
2. The tens digit of k + 4 is 2
Answer in my opinion: "A"

let the 3 digits of k be XYZ.
where Z is not zero
statement1:
when Z is not zero, it means that Z = [1-9]. for K+3 => Z+3 and carry added to Y, if there is any.
if Z = 1 then K(which is XYZ)+9 = then k => X-thousands place, (Y+1)-tens place, 0-units place
if Z = 9 then K(which is XYZ)+9 . maximum Z..even then only 1 is carried over to tens place in Y.
in both cases we end up adding 1 to tens place hence, tens place k+9 = 3 means tens place was "2".
statement2:
not sufficient..
Top
Newbie | Next Rank: 10 Posts
Posts: 9
Joined: Tue Mar 24, 2009 7:11 pm

by neel_mutum » Tue Sep 21, 2010 12:55 am
Question:
Tom, Jane, and Sue each purchased a new house. The average price of the three houses was 120,000. What was the median price of the three houses?
1. The price of Tom's house was 110,000
2. The price of Jane's house was 120,000
.... in order to get median value.. we'll have to arrange in ascending order..
.. statement2 says Jane's House = 120,000
which means the other two will be 240,000. now if 240,000 is split in equal then 120,000 each .. median is 120,000.
even if we dont arrange equal.. 120,001 and other will be 119,999.. 120,000 becomes median!
... so i guess statement2 is sufficient... "B"
Top
User avatar
Legendary Member
Posts: 1460
Joined: Tue Dec 29, 2009 1:28 am
Thanked: 135 times
Followed by:7 members

by selango » Tue Sep 21, 2010 1:45 am
If the units digit of the three-digit positive integer k is nonzero, what is the tens digit of k?
1. The tens digit of k + 9 is 3
2. The tens digit of k + 4 is 2
stmt1,

Tens digit of k+9 is 3.

Whatever the unit digit[1..9],when it added with 9,1 is added with tens digit.

So tens digit must be always 2 and when added with 1 makes it 3.

K=X2Z+9,where Z is any integer from 1 to 9

Suff

stmt2,

Tens digit of k+4 is 2.

Tens digit of k can be 1 or 2.

K=X2Z+4,where Z is any integer from 1 to 5

K=X1Z+4,where Z is any integer from 6 to 9

Insuff

Pick A
--Anand--
Top
Junior | Next Rank: 30 Posts
Posts: 12
Joined: Sat May 22, 2010 11:36 pm
Thanked: 3 times

by msbinu » Tue Sep 21, 2010 8:00 am
Hi Selango
Tens digit of k+9 is 3.

Whatever the unit digit[1..9],when it added with 9,1 is added with tens digit.

So tens digit must be always 2 and when added with 1 makes it 3.


I think this is not right . What if the unit digit of K is 0 , Then the statement "Whatever the unit digit[1..9],when it added with 9,1 is added with tens digit. " is wrong . It wont add one. And the 10th digit will be 3.

IMO ANs is E.
What is the OA for this
Top
User avatar
Newbie | Next Rank: 10 Posts
Posts: 5
Joined: Wed Aug 11, 2010 2:57 pm

by gmatster » Tue Sep 21, 2010 9:33 am
msbinu wrote:Hi Selango
Tens digit of k+9 is 3.

Whatever the unit digit[1..9],when it added with 9,1 is added with tens digit.

So tens digit must be always 2 and when added with 1 makes it 3.


I think this is not right . What if the unit digit of K is 0 , Then the statement "Whatever the unit digit[1..9],when it added with 9,1 is added with tens digit. " is wrong . It wont add one. And the 10th digit will be 3.

IMO ANs is E.
What is the OA for this
The question states "units digit of...k is nonzero", therefore it should be A
Top
Junior | Next Rank: 30 Posts
Posts: 12
Joined: Sat May 22, 2010 11:36 pm
Thanked: 3 times

by msbinu » Wed Sep 22, 2010 5:23 am
The question states "units digit of...k is nonzero", therefore it should be A
Ohh .. I missed that .... My mistake :)
Top
Post new topic Post Reply
• Page 1 of 1